Abstract : The AFRPL has completed a series of tests to evaluate a potential replacement for the free siphon employed on the High Altitude Supersonic Target (HAST) vehicle. These tests were initiated following the demonstrated failure potential of the original free siphon device used on the HAST. The test article consisted of an 'off-the-shelf' stainless steel welded metal bellows to replace that part of the siphon which originally consisted of a teflon-covered stainless steel helical spring. (Modified author abstract)